Filter apparatuses of the type used for filtering particulate matter from fluid sometimes include a filter housing having an inlet for receiving the fluid with entrained particulate matter, and an outlet for delivering filtered fluid to a device needing fluid that is free of particulate matter. For example, a filter may be provided at the air inlet of an engine or an air compressor to remove dust, water, or other particulate matter that could cause damage to the engine or compressor if it were not removed from the air entering the engine or compressor.
In such filters, the bulk of the particulate matter is typically removed by a filter element that is installed within the filter housing in such a manner that the fluid must flow through the filter element, in traveling from the inlet to the outlet of the filter. The filter element typically includes a filter pack of porous filter material, which removes particulate matter from the fluid. Over time, the filter pack of the filter element becomes plugged or coated with particulate matter, necessitating removal and replacement of the filter element, in order for the filter element to continue in its function of supplying particulate-free fluid at the outlet of the filter.
A seal arrangement is provided at a juncture of the filter element in the housing, so that the fluid to be filtered cannot bypass the filter element while passing through the filter. Specifically, in one commonly utilized prior approach to providing a fluid filter, the filter element includes a media pack, a mounting flange attached to the inlet end of the media pack, and a seal support frame, which includes an annular axial extension thereof that projects axially from the outlet end of the media pack for supporting a seal. The seal is configured to seal radially and/or axially against the inner surface of the housing.
The seal support frame, of such prior filter apparatuses, typically includes integral webs extending completely across the outlet end of the media pack. These webs are sometimes provided for the purpose of resisting pressure forces acting on the media pack, which could cause the center of the media pack to bow outward in a downstream direction. It is heretofore been believed, by those having skill in the art, that such seal support frames having integral webs extending completely across the outlet face of the media pack were particularly necessary in media packs formed by stacking or coiling layers of corrugated filter material for a so-called “fluted filter,” in order to prevent the center of the filter media pack from telescoping in a downward direction under maximum rated inlet fluid pressure, particularly where the media pack is saturated with dirt or moisture. U.S. Pat. Nos. 6,190,432 and 6,610,117 to Gieseke, et al. disclose filter packs having seals attached to axially extending annular portions of a seal support frame which includes integral webs extending completely across the face of a media pack.
Having the seal mounted on an axially extending annular extension of a seal support frame, as has been done in the past, together with the space occupied by the webs at the outlet end of the filter pack, undesirably consume a significant portion of the volume inside of the housing, and in some instances cause the housing to be larger than it would have to be if the webbed, axially extending, seal support frame could be eliminated.
It is desirable, therefore, to provide an improved filter element, and filter apparatus in a form which better utilizes the volume inside of the cavity of the filter housing, while still providing means for precluding telescoping of the filter element.